There are many applications in industry where a variety of liquids are to be mixed in accordance with a predetermined recipe or formula. Examples of such industries include paint, pharmaceutical and health care, and food and beverage industries. In such applications, the conventional options of conveying the variety of liquids are:
1. measuring the variety of liquids into a portable liquid transport and discharging them into the processing tank for mixing;
2. by manually valving at the source tank or common header, measuring the variety of liquids and conveying them through suitable conduits into the processing tank;
3. a mixing or processing tank is to be connected to a series of liquid source tanks and for a time necessary to obtain transfer of a desired quantity of liquid from each source tank to the mixing or processing tank.
Typically, the above options are carried out by one or more operators. Mixing of the liquids at the processing tank may be on a batch-type basis, or may be in a continuous operation in a static mixer or the like.
A general object of the present invention is to provide a liquid delivery system of the described character in which sequential connection of the mixing or processing tank to the several source tanks is accomplished automatically, without operator intervention, and in such a way as to avoid either contamination of the liquids from malfunctioning valves leading directly to a process tank or to a common header with a previous liquid passing through the common header on the one hand, or leakage of the liquid to the surrounding environment on the other. Another and more specific object of the present invention is to provide a liquid delivery system of the described character that is economical to implement, and that provides reliable service over an extended operating lifetime.